Devil's claw (Harpagophytum procumbens) originates from the Kalahari and Savannah desert regions of South and Southeast Africa. In these parts of the world, devil's claw has historically been used to treat a wide range of conditions including fever, malaria, and indigestion. The medicinal ingredient of the devil's claw plant is extracted from the dried out roots.

Currently, the major uses of devil's claw are as an anti-inflammatory and pain reliever for joint diseases, back pain, and headache. There is currently widespread use of standardized devil's claw for mild joint pain in Europe.

These uses have been tested in humans or animals. Safety and effectiveness have not always been proven. Some of these conditions are potentially serious, and should be evaluated by a qualified healthcare provider.

GRADE *

There is increasing scientific evidence suggesting that devil's claw is safe and beneficial for the short-term treatment of pain related to degenerative joint disease or osteoarthritis (8-12 weeks), it may be equally effective as drug therapies such as non-steroidal anti-inflammatory drugs like ibuprofen (Advil®, Motrin®), and it may allow for dose reductions or stopping of these drugs in some patients. However, most studies have been small with flaws in their designs. Additional well-designed trials are necessary before a firm conclusion can be reached.

B

There are several human studies that support the use of devil's claw for the treatment of low back pain. However, most studies have been small with flaws in their designs, and many have been done by the same authors. Therefore, although these results can be considered promising early evidence, additional well-designed trials are necessary before a firm conclusion can be reached. It is not clear how devil's claw compares to other therapies for back pain.

B

Traditionally, devil's claw was commonly used as an appetite stimulant, and this remains a popular use. However, there is no reliable scientific evidence in this area, and it remains unclear if devil's claw is beneficial as an appetite stimulant.

C

Devil's claw is used to treat several types of pain, including osteoarthritis and low back pain. One case report indicates it may also be helpful for pain due to bone metastases. More research is needed in this area before a conclusion can be drawn.

C

Devil's claw is popular as a digestive tonic for the relief of constipation, diarrhea, and flatulence. However, there is no reliable scientific evidence in this area, and it remains unclear if devil's claw is beneficial for these uses.

C

* Key to grades

A: Strong scientific evidence for this useB: Good scientific evidence for this useC: Unclear scientific evidence for this useD: Fair scientific evidence for this use (it may not work)F: Strong scientific evidence against this use (it likley does not work)

Tradition / Theory
The below uses are based on tradition, scientific theories, or limited research. They often have not been thoroughly tested in humans, and safety and effectiveness have not always been proven. Some of these conditions are potentially serious, and should be evaluated by a qualified healthcare provider. There may be other proposed uses that are not listed below.

In general, a liquid extract (1:1 in 25% ethanol) of 0.10-0.25 milliliter three times daily has been used. For appetite loss or stomach discomfort, 1.5 grams daily in decoction or preparations with adequate bitterness has been used. For low back pain or osteoarthritis, 2-9 grams daily of crude extract or equivalent amounts of extract has been used. As tablets, 600 to 1,200 milligrams (standardized to contain 50 to 100 milligrams of harpagoside) by mouth three times per day has been used. For treatment of painful osteoarthritis, treatment for 2-3 months is often recommended. A doctor should be consulted if symptoms continue for longer.

Children (younger than 18 years)

Not recommended in children. The dosing and safety of devil's claw have not been studied thoroughly in children, and safety is not established.

Safety
The U.S. Food and Drug Administration does not strictly regulate herbs and supplements. There is no guarantee of strength, purity or safety of products, and effects may vary. You should always read product labels. If you have a medical condition, or are taking other drugs, herbs, or supplements, you should speak with a qualified healthcare provider before starting a new therapy. Consult a healthcare provider immediately if you experience side effects.

Allergies

People with allergies to Harpagophytum procumbens should avoid devil's claw products.

Side Effects and Warnings

At recommended doses, devil's claw is traditionally believed to be well tolerated. Whether use of devil's claw for longer than 3-4 months is safe or effective is unknown.

There are reports of headache, ringing in the ears, loss of taste and appetite, gastrointestinal upset, and diarrhea in those taking this herb. Devil's claw may affect levels of acid in the gastrointestinal tract and should be avoided by people with gastric (stomach) or duodenal (intestinal) ulcers. Devil's claw should be used cautiously in patients with gallstones.

Devil's claw may change the rate and force of heartbeats (chronotropic and inotropic effects). Individuals with heart disease or arrhythmias (abnormal heart rhythms) should consult their cardiologist or primary care physician before taking devil's claw.

In theory, devil's claw may lower blood sugar levels. Caution is advised in patients with diabetes or hypoglycemia, and in those taking drugs, herbs, or supplements that affect blood sugar. Serum glucose levels may need to be monitored by a healthcare provider, and medication adjustments may be necessary.

In theory, devil's claw may increase the risk of bleeding. Caution is advised in patients with bleeding disorders or taking drugs that may increase the risk of bleeding. Dosing adjustments may be necessary. Patients may need to stop taking devil's claw before some surgeries, and should discuss this with their primary healthcare provider.

Devil's claw products may be contaminated with other herbs, pesticides, herbicides, heavy metals, or drugs.

Pregnancy and Breastfeeding

Devil's claw may stimulate contractions of the uterus and cannot be recommended during pregnancy and breastfeeding. Patients should be aware that many tinctures contain high levels of alcohol and should be avoided during pregnancy.

Devil's claw may lower blood sugar levels. Caution is advised when using medications that may also lower blood sugar. A qualified healthcare provider should monitor patients taking drugs for diabetes by mouth or insulin closely. Medication adjustments may be necessary.

In theory, devil's claw may have an additive effect if taken with drugs used for pain, inflammation, high cholesterol, and gout. Drugs used for malaria may also interact.

Devil's claw may increase stomach acidity and therefore may affect drugs used to decrease the amount of acid in the stomach, such as antacids, sucralfate, ranitidine (Zantac®), and esomeprazole (Nexium®). Individuals taking any of these drugs should consult a qualified healthcare professional, including a pharmacist, before taking devil's claw.

Because devil's claw may affect heart rhythm, heart rate, and the force of heartbeats, individuals taking prescription drugs such as antiarrhythmics or digoxin (Lanoxin®) should consult their healthcare providers before taking devil's claw.

In theory, devil's claw may increase the risk of bleeding when taken with drugs that increase the risk of bleeding. Some examples include aspirin, anticoagulants ("blood thinners") such as warfarin (Coumadin®) or heparin, anti-platelet drugs such as clopidogrel (Plavix®), and non-steroidal anti-inflammatory drugs such as ibuprofen (Motrin®, Advil®) or naproxen (Naprosyn®, Aleve®).

Interactions with Herbs and Dietary Supplements

In theory, devil's claw may lower blood sugar levels. Caution is advised when using herbs or supplements that may also lower blood sugar. Blood glucose levels may require monitoring, and doses may need adjustment.

In theory, devil's claw may interfere with other herbs and dietary supplements that affect heart rhythm, heart rate, and the force of heartbeats. Notably, bufalin/Chan Suis is a Chinese herbal formula that has been reported as toxic or fatal when taken with cardiac glycosides.

Devil's claw may add to the effects of herbs and dietary supplements that are used for pain or inflammation. Devil's claw may also interact with herbs or supplements used to treat malaria.

Devil's claw may reduce cholesterol concentrations and may add to the lipid-lowering effects of fish oil or garlic.

In theory, devil's claw may increase the risk of bleeding when taken with herbs and supplements that are believed to increase the risk of bleeding. Multiple cases of bleeding have been reported with the use of Ginkgo biloba, and fewer cases with garlic and saw palmetto. Numerous other agents may theoretically increase the risk of bleeding, although this has not been proven in most cases.

The information in this monograph is intended for informational purposes only, and is meant to help users better understand health concerns. Information is based on review of scientific research data, historical practice patterns, and clinical experience. This information should not be interpreted as specific medical advice. Users should consult with a qualified healthcare provider for specific questions regarding therapies, diagnosis and/or health conditions, prior to making therapeutic decisions.